A Most Curious Array of Breakdowns

RAY: Here's what they all had in common, their batteries all went dead.

The reason their batteries went dead is that, unlike Jim's truck,
which didn't have an air conditioner, they were sitting there with
the AC on -- and they weren't moving.

The alternator charges the battery when you're moving. It's not
designed to keep your battery charged for three hours or four hours
at a time, when you're not moving.

The charging system wasn't producing enough current to keep the
battery charged and run the AC, which requires an electric fan to
cool the condenser, a compressor clutch, and a blower motor. Not to
mention, they probably had their laptop computers plugged in!

RAY: In fact, many modern cars also have their headlights on during
the day, including, in this case, the moving van, the SUVs and the
fancy Audi.

RAY: So who's our winner, Tommy?

TOM: The winner is Judith Cotes from Bellingham, Washington. And
for having her answer selected at random from among all the correct
answers that we got, Judith is going to get a twenty six dollar gift certificate to
the Shameless Commerce Division at cartalk.com. And with that
certificate she can almost get a brand-new Car Talk stainless steel
thermos.